THE PET HEALTH LIBRARY By Wendy C. Brooks, DVM, DipABVP Educational Director, VeterinaryPartner.com

More than you ever Wanted to Know about Anal Sacs, or Why is my Pet Scooting?

Click on the dog to start his tail wagging. Click again to zoom in and see the placement of the anal sacs (under the skin). (Requires the Shockwave Flash plug-in) Click once more to return to normal view.

What on Earth are Anal Sacs?

Anal sacs (also called anal glands) are two small glands just inside your pet's anus. The material secreted into these glands is thick and foul-smelling. Most animals can empty these glands voluntarily for scent marking or in self-defense, like a skunk might do.

Domestic animals have largely lost their ability to empty these sacs voluntarily. Walking around and normal defecation serves to empty the glands but some animals become unable to empty their glands at all on their own. The sacs become impacted and uncomfortable. Dogs with impacted anal sacs usually scoot their rear on the ground in an attempt to empty the glands. Some dogs will lick their anal area and other dogs will chase their tails. Cats often lick the fur off just under their tails.

What to do about Scooting?

The first step is to check the anal sacs when any pet has a history of scooting. The anal sacs can be emptied in one of two ways

Externally: A rag or tissue is held up to the anus and both sides of the anal area are squeezed. If the secretion is very pasty, this method may be inadequate to empty the sacs. Internally: A lubricated gloved finger is inserted in the anus and the sac is squeezed between thumb and forefinger into a tissue held externally. The full anal gland feels like a grape in the location as shown in the top illustration. The emptying procedure is repeated on the opposite side.

DIRECTIONS to try the Anal Sac Emptying Demonstration: (you must have the Flash plug-in to see the animation) Drag the gloved technician's arm to grab the cloth rag. Then, position the rag over the anus of the dog on the left to empty the anal sacs externally, or of the dog on the right to empty the anal sacs internally. Once you've successfully grabbed the rag and properly positioned it, the technician will take over and demonstrate the procedure. When done, you may drag the arm to take a new cloth rag and try again.

If the sacs have been emptied adequately, the scooting should resolve in a couple of days.

What if Scooting Continues?

If scooting continues for more than a few days after sac emptying, the sacs should be re-checked. For some individuals, it takes several sac emptyings in a row before the sacs stay emptied. If the sacs are empty and scooting is persisting, another cause (such as itchy skin, tapeworms, or even lower back pain) should be pursued.

What Happens If an Impacted Sac doesn't get Emptied?

An abscess can form and rupture out through the skin. This is a painful, messy and smelly condition often mistaken for rectal bleeding. If an anal sac abscess forms, it must be properly treated by your veterinarian. Antibiotics will be needed.

How often should Anal Sacs be Emptied?

This is a highly individual situation. The best recommendation is to let the pet tell you when the sacs are full. If the pet starts scooting again, it is time to bring him in.

What if My Pet's Sacs seem to Require Emptying all the Time?

To avoid the expense of having the sacs emptied, you can learn to empty them yourself at home, but most people feel it is well worth having someone else perform this service. A non-invasive technique that helps some patients is a change to a high fiber diet. This will produce a bulkier stool that may be more effective in emptying the sac as it passes by.

Anal Sacculectomy

If the sacs need to be emptied every few weeks or more, you may opt to have the sacs permanently removed. This procedure is complicated by many local nerves controlling fecal continence, any changes in the local musculature of the anal sphincter area can affect fecal continence, and anatomy is distorted with chronic anal sac problems. Draining tracts can develop after surgery if the gland is not completely removed. Still, despite these pitfalls anal sac removal is considered a relatively simple surgery by experienced surgeons.

Many people own pets for years without ever learning that anal sacs exist at all and the “old wive’s tale” that worms cause scooting erroneously continues. If you have further questions about anal gland disease, ask your veterinarian or click on the “Ask A Vet” feature on the home page of Veterinary Partner.

Date Published: 1/1/2001
Date Reviewed/Revised: 12/28/2008